Activated aluminas are attractive catalysts for processes such as petroleum hydrodesulfurization, isomerization reactions, the Claus reaction, the dehydrogenation of butane to give butenes and the dehydration of alcohols to give alkenes. One of the major problems related to the use of alumina catalysts is the deactivation by coke formation and pore plugging which limits the diffusion of substrates and products in and out the catalyst particles. It is known that the larger the contribution of micropores to the specific surface area and the wider the pore size distribution, the greater the enhancement in the deactivation rate. Thus, synthesis of aluminas with porosity properties comparable to those exhibited by high and all-silica mesoporous materials would be of industrial interest. The silica-based mesoporous materials developed by researchers at Mobil, e.g., M41S, were recently prepared by organizing silica with organic surfactants (See C. T. Kresge et al., Nature 1992, 359, 710-712 and J. S. Beck et al., J. Am. Chem. Soc. 1992, 114, 10834-10843). These materials can exhibit cubic or hexagonal symmetry, e.g., MCM-48 and MCM-41, respectively. Thermal decomposition of the surfactant allows for the development of narrow pore size distributions in the range 15-100 .ANG. and BET specific surface areas above 1000 m.sup.2 /g. Mesoporous materials are not restricted to silica since the MCM-41 type materials have been reported recently for oxides of titanium (See D. M. Antonelli et al., Angew. Chem. Int. Ed. Eng. 1995, 34, No. 18, 2014-2017), antimony, and lead (See Q. Huo et al., Nature 1994, 368, 317-321 and Q. Huo et al., Science 1995, 269, 1242-1244). Our own early work on pure-alumina mesoporous materials revealed that aqueous solutions of cationic surfactants do not yield mesophases and, as already reported in the literature (Q. Huo et al., Science 1995, 269, 1242-1244), that aqueous solutions of anionic surfactants, such as alkyl phosphates or sodium dodecylbenzenesulfonate, can promote the formation of thermally unstable lamellar phases as the only mesophases.
It is also known to synthesize mesoporous crystalline materials containing such oxide materials as silica and alumina (see, for example, U.S. Pat. Nos. 5,057,296 to J. S. Beck and 5,198,203 to C. T. Kresge et al.) More recently, layered, non-porous aluminas have been synthesized using anionic surfactants (see, for example, Nature, Vol. 368, Mar. 24, 1994, pp. 317-321 and Chemistry of Materials, 1994, Vol. 6, pp. 1176-1191).
In addition to the foregoing prior art disclosures, certain other disclosures exist in the art showing alumina-containing, relatively large macroporous structures with an average pore diameter of over 100 .ANG.. Examples such disclosures may be found, for example, in European Patent Publication Nos. 363,910 and 365,801.
Recently, the synthesis of all-alumina mesoporous materials has been mentioned by S. A. Bagshaw et al, Science, Vol. 269, Sep. 1, 1995, pp. 1242-1244. The procedure, which is not given in detail in that publication, involves the use of polyglycols as surfactants. The solids after calcination at 873 K can develop a material having a BET specific surface area of 420 m.sup.2 /g and a pore diameter of 48 .ANG..